The error “Closure: ()=> Map from Function ‘toJson’” usually occurs when there is an issue with converting a class instance to a JSON object. Here are methods to solve this issue
Step-by-Step Guide:
- Check the
toJson
Method: Ensure yourtoJson
method is correctly implemented. It should return aMap<String, dynamic>
.
class MyClass {
String name;
int age;
MyClass({required this.name, required this.age});
Map<String, dynamic> toJson() {
return {
'name': name,
'age': age,
};
}
}
Avoid Using Closures in toJson
: Ensure no closures are being returned by the toJson
method. It should directly return a map.
Check the Usage of toJson
: Make sure you are calling toJson
properly in your code.
MyClass instance = MyClass(name: 'John', age: 30);
Map<String, dynamic> json = instance.toJson();